1. Field of the Invention
The invention relates to a chemical treatment system and, more particularly, to a substrate holder for a high throughput chemical treatment system.
2. Description of Related Art
In material processing methodologies, various processes are utilized to remove material from the surface of a substrate, including for instance etching processes, cleaning processes, etc. During pattern etching, fine features, such as trenches, vias, contact vias, etc., are formed in the surface layers of the substrate. For example, pattern etching comprises the application of a thin layer of radiation-sensitive material, such as photo-resist, to an upper surface of a substrate. A pattern is formed in the layer of radiation-sensitive material using a lithographic technique, and this pattern is transferred to the underlying layers using a dry etching process or series of dry etching processes.
Additionally, multi-layer masks, comprising a layer of radiation-sensitive material and one or more soft mask layers and/or hard mask layers, may be implemented for etching features in the thin film. For example, when etching features in the thin film using a hard mask, the mask pattern in the radiation-sensitive layer is transferred to the hard mask layer using a separate etch step preceding the main etch step for the thin film. The hard mask may, for example, be selected from several materials for silicon processing including silicon dioxide (SiO2), silicon nitride (Si3N4), and carbon. Furthermore, in order to reduce the feature size formed in the thin film, the hard mask layer may be trimmed laterally. Thereafter, one or more of the mask layers and/or any residue accumulated on the substrate during processing may be removed using a dry cleaning process before or after the pattern transfer to the underlying layers. One or more of the pattern forming, trimming, etching, or cleaning process steps may utilize a dry, non-plasma process for removing material from the substrate. For example, the dry, non-plasma process may comprise a chemical removal process that includes a two-step process involving a chemical treatment of the exposed surfaces of the substrate in order to alter the surface chemistry of these exposed surface layers, and a post treatment of the chemically altered exposed surfaces in order to desorb the altered surface chemistry. Although the chemical removal process exhibits very high selectivity for the removal of one material relative to another material, this process suffers from low throughput thus making the process less practical.
Etch processing is normally performed using a single substrate processing cluster tool, comprising a substrate transfer station, one or more process modules, and a substrate handling system configured to load and unload a single substrate into and out of each of the one or more process modules. The single substrate configuration allows one substrate to be processed per chamber in a manner that provides consistent and repeatable process characteristics both within-substrate and from substrate-to-substrate. While the cluster tool provides the characteristics necessary for processing various features on a substrate, it would be an advance in the art of semiconductor processing to increase the throughput of a process module while providing necessary process characteristics.